Problems with rotation and scale importing blender object to unity? Replicate unity cube?
Yes, Blenders scale is different, if you are using FBX (which i would recommend for Unity likes it), there is an export options called: Apply Transform (Experimental!). This works for me, otherwise, scale your final mesh down to compensate (Unity's scale is 100x smaller, so it makes the cube's scale 100x100x100, you can also adjust the mesh import scale in Unity, instead of compensating in Blender).

In Blender, if you make any changes to the rotation in object mode, you need to apply that rotation (CTRL - A) before it exports it. Also, the reason the rotation is wrong is due to Unity using the Y axis as its up axis, and for Blender this is Z. You can compensate by making the up axis of your mesh the Y axis in blender. See posts like this for more info: http://answers.unity3d.com/questions/174832/stopping-the-270-degree-fbx-default-rotation-on-im.html

If you are still experiencing issues something is going wrong in Unity, and you should post the issue in the Unity section, with your script included. And good luck and have fun learning!